1. Field of the invention
This invention relates generally to medical devices, and more particularly to a balloon system for treating sinusitis or allergic rhinitis.
2. Related art
Sinusitis is a common Ear-Nose-Throat (ENT) disease for the person between 5 and 79 years old. Its incidence takes 15 percent of the population with trend toward gradual increase. Sinus is aerated cavities of the facial bone around the nasal cavity. The inflammation of the sinus causes the expansion of locations of pathological changes, which blocks the pathway for the nasal air and nasal mucus, and results in nasal mucus countercurrent, build up pressure and thus cause headache. In addition to headache, typical symptoms of acute sinusitis include nasal congestion, thick nasal mucus, temporary olfactory dysfunction, chills, fever, inappetence, constipation, general malaise and so on. Children and infants may have the symptoms including vomiting, diarrhea, coughing and so on. The thick nasal mucus may irritate the throat, and result in throat problem such as pharyngolaryngitis and so on. Intense acute sinusitis may result in ophthalmic infections. However, the complication of acute sinusitis, such as orbital infections, rarely occurs due to the wide application of antibiotic in recent years.
The functional nasal endoscopic surgical procedure (FESS) is effective for the acute sinusitis and chronic sinusitis. Tissue and bone with pathological changes can be removed precisely to expand the ostium of the sinus and to restore the normal physiological function of the sinus. The nasal endoscopic surgical procedure is minimally invasive compared with the traditional sinusitis surgery.
However, nasal endoscopic surgical procedure is expensive and not thorough. The resulted relapse will cause the repeated treatment, which costs a lot and brings heavy mental and economic burdens to patients.
Allergic rhinitis, also known as nasal allergies, is an upper respiratory disease with complicated pathogeny. The allergic rhinitis caused by pollen allergy is also called pollenosis, hay fever, or seasonal allergic rhinitis.
Usually, once the patient contacts with or inhales allergens, the IgE (immunoglobulin E) in vivo will cause the mast cells to release histamine and thus cause allergic reactions. Allergens are the antigens inducing and reacting with specific IgE antibody. Most allergens are derived from animals, plants, insects, fungus or other specific substances. Allergens can be divided into inhalational allergens and alimentary allergens. The inhalational allergen is the main reason of allergic rhinitis. Symptoms of allergic rhinitis mainly include telangiectasis, increased permeability, increased glandular secretion, and eosinophilic infiltration, etc. Proliferative changes in the mucosa epithelium, mucosal hypertrophy and polypoid lesion will be resulted if above symptoms are recurrent. It has flu-like symptoms, which primarily include nasal itching, nasal congestion, snot, sneezing and watery rhinorrhea (ninny nose), etc. These symptoms are intermittent and recurrent with pale edema of nasal mucosa. The worse will evolve into sinusitis, asthma or ear infections.
Drug therapies don't have positive effect for allergic rhinitis. Surgical therapies for allergic rhinitis mainly comprise nerve block surgery, low-temperature plasma surgery, inferior turbinate mucosa surgery, parasympathetic-excitability-decreasing surgery and so on. However, both the recurrence rate and cost of these surgeries are high.
In addition, special medical instruments, such as a nasal irrigator, have been developed to treat refractory nasal disease such as sinusitis. CN202314874U discloses a sinusitis therapy tube for cleaning the nasal cavity, wherein, injected liquid medicine is used to irrigate and immerse the nasal cavity, and then the pus is discharged via a discharging pipe. As compared with ordinary nasal spray, the invention can clean the nasal cavity better, which is beneficial for the patient to recover from inflammation. However, the disadvantage of these irrigators is that the nasal sinus ostium of the patient is narrow or even blocked, thus the liquid medicine can be irrigated only to the turbinate rather than to the interior of the frontal sinus and maxillary sinus, however, the interior of the nasal sinus is just the source of the inflammation. Actually, even if the liquid medicine can be irrigated to the interior of the nasal cavity, the brief contact with medicine can only alleviate the inflammation, and after the effect of the medicine disappears the narrow nasal sinus ostium causes the interior of the nasal cavity back to the status before the irrigation. Therefore, nasal irrigation is only used as an adjunctive therapy rather than a dominant technology during nasal cavity surgery or treatment.
CN201676386U discloses a balloon catheter for treating rhinitis and sinusitis, which is developed from cardiovascular dilation technology. All parts of the catheter (i.e. the first, second and third connector parts) are permanently connected with one another in structure, to form a whole which cannot be disassembled freely. This kind of catheter therapy technology based on cardiovascular disease treatment has been applied to nasal sinus open surgery by American engineers in 2002, and certificated by FDA in 2005, and finally approved for clinical application. The application of the balloon catheter disclosed in the patent is similar to PTCA technology (Percutaneous Transluminal Coronary Angioplasty), namely, with the euthyphoria in nasal endoscopy, an uninflated pressure-endurable balloon is disposed in the sinus ostium to be opened, then the balloon is inflated for a period of time, thus the balloon will press and expand the sinus ostium, so that the inelastic bone structure fractures and expands, and the elastic mucosa tissue is pressed and deformed, consequently the sinus ostium is expanded and smooth and continuous airway is obtained. Nowadays, PTCA technology application in tubular artery operation decreases year by year, for the reason that the narrow part of the blood vessel temporarily expanded by the balloon is easy to narrow even close again. The similar situation can also happen to balloon Sinuplasty technology, that is to say, although the balloon catheter disclosed by CN201676386U is convenient and efficient, after the balloon is removed, the expanded passage is easy to be blocked once again due to the patients' pathological regeneration or tissue recoil, thus the therapy in the patient cannot provide sufficient time for treating the diseases such as sinusitis until complete cure.
US20070250105A1 discloses a device and method for treatment of sinusitis, which refers to an expanded balloon delivered into the maxillary sinus ostium through nasal cavity or maxillary sinus puncture for supporting the sinus ostium. All parts of the balloon system including the balloon are permanently connected with one another and cannot be disassembled freely, therefore, the balloon system is entirely taken out after expanding the maxillary sinus ostium. The disadvantage of ordinary balloon sinuplasty technology is referred to in CN201676386U and not described here. US20070250105A1 further refers to a support (such as coronary stent) implanted into the sinus ostium, wherein the support is independent from the balloon system and used to maintain the sinus ostium unblocked. However, as the structure of the nasal cavity is different from that of the coronary, and the nasal cavity has complex structure with individual difference, ordinary supports may not be adequate for the nasal cavity structure, and the implanted support increases the cost of the surgery and patient's burden.
Consequently, the expanded airway must be maintained for enough time, and medicines should be continuously provided under this condition, such that the diseased region can be cured radically and tissue function can be recovered, thus the possibility of recurrence of airway blockage is minimized and the surgery wound and cost are decreased as much as possible.